Multiprotocol Label Switching (MPLS) networks are an attractive alternative for use in very high speed backbone networks. On entering the network, data packets for a particular link are assigned a label. Packet-forwarding decisions are made solely on the contents of this label without the need to examine the packet itself. This allows creation of end-to-end circuits across any type of transport medium, using any protocol. The primary benefit is to eliminate dependence on a particular open systems interconnection (OSI) model data link layer technology, such as Asynchronous Transfer Mode (ATM), Frame Relay, Synchronous Optical Networking (SONET) or Ethernet, and eliminate the need for feeder networks to satisfy different types of traffic.
MPLS networks often include thousands of nodes (switches, routers, etc.) and determining the best routing is a great challenge. Not only must the path attached to a label be as fast as possible, it must account for other traffic and for disabled loads or links and issues such as quality of service. Currently, techniques such as traffic engineering fast reroute (TE FRR) or loop free alternative (LFA) are used for point to point (P2P) label switch path's (LSP's) fast reroute (FRR). With the complexity of MPLS signaling, the TE FRR or LFA solutions are not easy for users to deploy and maintain. By using the PCE controller to calculate and program the network nodes for the primary and protect/secondary LSP path, the local protection services for LSPs are provided through the centralized system without the complexity of the distributed MPLS signaling.